


Cross the Threshold

by RexBrickowski



Category: The LEGO Movie (2014)
Genre: First Time, I just really love these three, Lime, Multi, Polyamory, They're just nervous and silly dorks, they deserve the world
Language: English
Status: Completed
Published: 2019-09-14
Updated: 2019-09-14
Packaged: 2020-10-18 17:17:15
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,653
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20642816
Author URL: https://archiveofourown.org/users/RexBrickowski/pseuds/RexBrickowski
Summary: Rex, Lucy, and Emmet have been living together for a few months now. They've since accepted their feelings for one another, and have been enjoying a happy, commited relationship...Mostly.Rex constantly feels like he's trapped on the other side of a barrier.And technically, he is...But all he needs to do in order step through is turn the handle.





	Cross the Threshold

**Author's Note:**

> Once again! Thank you MalisonQuill!!!!! YOU'RE A FEKIN BLESSING
> 
> Now! I hope ya enjoy the OT3 fluff!!! ♡

Rex paced outside of the bedroom door, hugging his elbows tightly to himself, red-faced and scowling deeply.

The first time Emmet and Lucy had gone into the bedroom together all those months ago, they had given Rex their explicit permission to enter at any time, but… the thought of opening that door caused his stomach to twist into knots. He had never gotten farther than simply standing outside… he couldn't even bring himself to grab the handle. 

He paused right outside of the door, turning to face it with a pained grimace. 

He should just walk away. Pacing in the hall and arguing with himself over whether or not to go inside wasn't helping anyone. He clearly wasn't ready after all. 

… 

He took a step closer, turning his head to aim his ear at the wood, listening. 

It was silent for a moment. Then he heard a soft rustle, a body moving over fabric. A quiet murmur. 

Rex held his breath and leaned in slightly, face turning a deeper shade of red, anticipation causing his skin to prickle slightly. 

Then came Emmet's unmistakably bubbly giggle, followed by a deep, loving sigh from Lucy.

Rex fought back the sudden animalistic urge to tear the door off of its hinges, to shatter the wooden barrier with a single punch. It felt as if a giant magnet were attracting every atom of his being, dragging him towards them… It took all his willpower to resist its pull. 

It was all _ too much _. 

Rex quickly took a step back again, panting hard. His clothes were suddenly too tight, keeping him from breathing properly… 

That had been a mistake. 

He turned away from the door, running a hand through his hair to soothe his frazzled nerves.

He couldn't stay here if he wasn't going to go inside. This would drive him crazy.

With a sigh of defeat, he turned and started walking down the hall, movements reluctant and sluggish. 

He was sick of going into the bathroom alone and locking himself inside, of the cold showers, the loud music, the empty fantasies… They were _ right in there _ , behind that fucking door. **Fuck** fantasies, they were _ waiting _ for him! It was simple, he could picture it now… He'd open the door, and they would… they would be…

Rex groaned, leaning his forehead against the wall.

He had to stop torturing himself like this! Thinking this way was making things so much worse. 

He tilted his head slightly, looking back at that infuriating door. 

… He was going to go in. Tonight was the night.

He stood up straight again, but immediately his determination wavered. 

Those few steps he had taken towards the bathroom had somehow stretched over a mile, the bedroom suddenly impossibly far away. 

Going into the bathroom would be easier… It was safe in there, where he'd be alone… there was nothing to be worried about when he was by himself. 

_ Why are you worried? _ Rex scoffed to himself. _ What the hell would you have to be nervous about? _

Well, to answer that question… A lot, actually. 

He had no idea what he was doing.

He couldn't remember the last time he had so much as _ seen _ another person naked.

Rugged charm and well-sculpted features could only get you so far… He was seriously lacking in experience. And this was far from Lucy and Emmet's first time since starting their new lives in Syspocalypstar.

And... 

There was another fear, too. One he didn't dare address, but that nagged at his thoughts, hung in the back of his mind like a dark cloud. 

What if they didn't actually want him in there? What if they were perfectly happy without him? 

Rex once again ran a hand through his hair, letting out his breath in a quiet puff of air.

Okay. Enough stalling. 

These were his _ partners _ he was talking about. No one knew them better than himself. If they told him he was welcome, then they meant it. 

He could trust them. 

Rex sighed, shaking his head as he reached down for the handle--

_ Wait, the handle?? _

Rex's hand closed around the metal knob, and he froze. When had he gotten back to the bedroom door??

He heard the bed springs squeak slightly. 

… It wasn't too late to back out! 

He was already starting to release the doorknob again and turn away, when--

_ "Rex? Is that you?" _

Fuck. 

She had heard the handle move.

Rex stayed where he was, completely frozen, going full deer-in-the-headlights.

There was a moment of silence. _ "... Sorry Emmet, maybe I'm just hearing things…" _

The bed creaked again slightly. 

_ "It's okay. He'll come in when he's ready." _

_ "Why don't we just… bring him in with us next time? I don't know why he's so nervous… He just needs to get comfortable, and he can't do that unless he's, you know, actually in here." _

_ "Hey, that's hardly fair to him! It has to be a decision he makes himself, we can't just… tell him that he's ready. Besides… We both know it'll be worth the wait." _

_ "I know… I just… I'm tired of waiting." _

Emmet chuckled. _ "Yeah, I know." _

His body moving of its own volition again, Rex turned the handle slightly.

Lucy and Emmet fell silent, and Rex balked slightly. 

No… not this time. 

The handle clicked. Rex slowly pushed the door open, ignoring the thundering of his heart in his ears, putting on an expression that was much calmer than he felt…

And there they were. 

Emmet and Lucy were sitting up in bed, looking at the doorway in surprise. Unable to help himself, Rex's eyes strayed from their stunned faces and flicked over the sheets bunched around their legs, then their naked torsos, lingering for a moment on Lucy's bare breasts, on Emmet's soft middle.

"Rex!" Lucy sat up a little straighter, a smile brightening her face.

She always looked so adorable with her hair down. It made her look so much younger somehow… Right now especially, with her eyes shining like that.

"You're here!!" There was a beat, and suddenly Emmet blushed hard, pulling the sheets up to his chin. "Ehm… G-glad you… that you're…" 

He paused, glancing down and fiddling with the sheets in his hands for a moment, before looking back up at Rex with an even redder blush than before.

_ "Hi..." _

Rex blinked, aware that his face was burning red hot again. But a smile was tugging at the corners of his mouth now, too.

"Well then… 'hi' to you too."

Lucy gave a small snort of laughter and tried to tug the sheets from Emmet's hands, who gave a quiet squeak of indignation. 

"Was worried you might not make it tonight, Dangervest."

Oh god that was _ cute _. 

"Well, what can I say, I'm full of surprises." Rex leaned against the door frame, fighting back laughter as he watched Lucy wrestle with Emmet, who seemed completely dead-set on keeping the sheets clutched to his chest. And here Rex had been thinking _ he _ was going to be the embarrassed one.

Lucy huffed and released the sheets again, rolling her eyes as Emmet triumphantly pulled them around himself. "It would seem our little boyfriend here is a bit body shy all of a sudden."

Emmet shot her a scandalized look, flushing.

Rex stood up straight again and slowly walked towards the bed, his casual expression masking his racing thoughts, and the drum solo his heart was currently playing. Emmet watched him with wide eyes, slowly sinking down into the sheets. 

Rex stopped at the side of the bed, crossing his arms and raising a brow ever so slightly. "Hey, Ems… you do realize that I'm _ literally _ the last person you need to be nervous around, right?"

Emmet opened and closed his mouth a few times, before biting his lip and looking away. "I… I guess, but… it's different for you, you're… Y-your body is…" Emmet trailed off, his eyes tracing over Rex's arms with a look of flustered dismay. 

Rex leaned down slightly, reaching out and taking hold of Emmet's hand holding the sheet. He kept his eyes locked on Emmet's as he gently guided his hand down, meeting little resistance from the stunned construction worker. Bit by bit his bare torso was exposed.

Rex gently rest Emmet's hand on his lap before letting go and straightening again, smirking slightly.

Emmet really didn't have any reason to be embarrassed. Despite his rather… _ plush _ midsection, his arms bore the kind of round, thick muscle that you earned from years of hard work. He was no bodybuilder like Rex, sure, but you could tell from just a glance that he was clearly strong. Just… cuddly, too.

You didn't need defined abs to be able to comfortably lift and carry 300 lbs of construction equipment. 

Rex nodded in approval, giving Emmet a lopsided grin. "There we go… There's my cute boyfriend."

Emmet _ squealed _.

He buried his face in his hands, bending over slightly, his blush spreading all the way to his neck and ears.

Lucy and Rex made eye contact, both of them barely suppressing laughter, beaming at one another. 

This man had _ no right _ being this adorable. 

"Y-you alright there, Ems?" Rex wrestled with his laughter as he reached over to gently touch Emmet's shoulder.

Lucy suddenly caught his wrist, startling him slightly. He hadn't noticed her move.

"Uh--" He turned to face her, and felt his heart do a frenzied flutter. 

Lucy slowly rose from the bed, still holding his wrist in a playfully dainty grip, until she was standing right next to him… Naked, confident, and _ beautiful _. 

He kept his eyes fixed on her face, knowing that the moment his gaze moved from hers, strayed downward… it would be all over for him.

"Hah… What…?"

She simply gave him a knowing smile, taking a step closer to him. Rex found himself instinctively leaning back, eyes widening.

She placed her other hand on his chest, gently fingering the top button of his vest. Rex swallowed hard, trying for a grin but feeling his facial muscles not really respond.

Lucy released his wrist and began slowly undoing the buttons of Rex's vest. She lowered her gaze to watch what her hands were doing, lifting the hem and carefully unhooking every button underneath with agonizing care.

Emmet slowly peeked through his fingers, his embarrassment gradually being forgotten as he watched Lucy put on her little show. 

Rex felt woozy. Was he going to pass out? No, no he wasn't. But he certainly did feel unsteady.

_ Oh God. She was so close. He could probably smell her shampoo. _

He focused on his breathing, like he did when meditating. Inhale through the nose, hold, exhale slowly until his lungs were empty. Repeat. 

_ Her skin looked so soft… Her shoulders had freckles too. _

Inhale through the nose. 

_ So did her arms. He hadn't thought about that, but it made sense that she would have freckles on more than just her face. It was so cute. _

Hold. 

_ Her hair wasn't just one shade of blue. Up close, it was possible to see that some strands were slightly darker, scattered throughout the sea of sky blue. _

Exhale until there was nothing left. 

_ How did she get it to frame her face so perfectly, even after her and Emmet's romp just a few moments ago? _

Repeat.....?

Rex had a sudden thought. He tried to push it aside, but it kept nagging at him, demanding he address it. It was so stupid, and yet… 

He let his eyes travel down. Past her hands, still on his chest; past her round and--Rex would not lie--_ very tempting _ breasts; and to her hips, where…

"... You shaved."

Lucy paused, hands on the second to last button of his vest, caught completely off guard by his comment. "... I… what??" 

Rex gestured weakly to her waist. "There's… There's no hair."

Lucy looked down at herself in surprise, and Rex could practically see the gears turning in her head as she processed what he meant… 

And then it was her turn for her face to turn bright red. 

"Well… Well, yeah, you know… It feels cleaner when it's smooth down there." 

The corner of Rex's mouth twitched upwards. "Really? That's the only reason why?" 

Lucy couldn't meet his eye. "... Well, yeah. Why would there be another reason…?" 

Emmet stifled a giggle, and Lucy shot him a look. He quickly clapped a hand over his mouth, but Rex was undeterred. 

He rubbed his chin thoughtfully. "You never seemed--you know, in my personal opinion--like the kind of girl that would shave… I figured you were one of those badass chics that didn't care." Rex shrugged, shaking his head. "Ah well, who am I to judge." 

"I don't care!" Lucy quickly interjected, huffing. "I don't!!" 

Rex turned to look over his shoulder at Emmet, who grinned back at him. "_ The lady doth protest too much, methinks _," he quipped in a fake accent. Emmet burst into muffled laughter, looking between Rex and Lucy with his hand held firmly over his mouth again. 

Lucy glared at the two men for a moment, before crossing her arms and looking at the ceiling with a groan. 

"Okay! Fine! You got me!" She turned back to her boyfriends, shooting each a stern look of disapproval. Her arms crossed a little tighter as she turned to the wall, blush deepening.

“… Yes. It matches my hair. _ Happy now? _”

Rex and Emmet looked at each other for a moment… and both of their faces lit up. 

_ "... No effing way." _

Lucy threw her hands into the air in exasperation. "**UGH** . I _ knew _ you were going to react like this!!"

"It's not a bad thing Lucy! It's really cute!" Emmet attempted to placate her, while simultaneously trying to hide his amusement. And failing. 

"Oh, you're going to have to let it grow now." Rex grinned, wiggling his brows.

"Godammit--No, I am _ not _ letting it grow." Lucy covered her eyes with one hand, giving a combined sigh/groan.

"Just for a little bit! Then you can shave it off again!" Emmet suggested hopefully. 

"Yeah! Just let us have a look!" 

"_ Not. Happening. _" Lucy firmly said with a scowl, before she changed her tune and gave them a pleading look. "Look, let's just… forget I ever told you, okay?"

"Okay, I'm sorry," Emmet quickly agreed.

Rex glanced at Emmet, then he looked back at Lucy with a devilish grin.

"...I bet it probably looks like cotton candy--"

"Rex. If you don't stop talking right now, I am locking you in the bathroom and not letting you out for the rest of the night."

Rex immediately snapped his mouth shut, looking chagrined.

So… She knew about that, huh. And based on Emmet's sheepish expression, he did too. 

_ Yikes. _

"Sorry, ma'am," Rex muttered, slipping his hands into his pockets with a quiet cough. 

_ "Thank you." _ Lucy stepped up beside him again, and in one fluid motion grabbed hold of the bottom of Rex's vest and gave it a hard yank. The last two buttons were roughly pulled free. Rex raised his hands defensively, giving a startled _ "Hey!!" _

Without a word, Lucy tugged his vest off, tossing it to Emmet, who fumbled with it before holding it, looking just as flustered as Rex felt.

"L-Luce! Wh--" 

"Revenge, Mr. Dangervest," Lucy said with a half smile, grabbing handfuls of his shirt. "I was _ going _ to take my time and play nice, but you've ticked me off a little, _ young man _." On the last two words, Lucy pulled him towards her so they were eye-to-eye… 

And suddenly her lips were on his.

They had kissed before, of course, all of them had, but _ never _ like this.

Her mouth pressed against him forcefully, her lips slowly moving over his skin until they were fit against his. Her tongue gently caressed his bottom lip, and he couldn't suppress a soft shudder. 

He wrapped his arms around her waist gently and let his lips part, any need for thought fading away as he closed his eyes. In turn, her grip on his shirt tightened as she leaned in closer. 

She let her tongue slip through the opening he had given her, slowly circling around his, and Rex felt his knees go weak.

Oh fuck. _ He was going to fall over. _

Rex reached behind him in vain for the bed, not remembering how far from it he had been standing. Fireworks were going off in his head, and the only thing he was truly aware of, the only thing he perceived, was the insistent, passionate affection of the woman pressed against him.

Then he felt a hand take his, gently guiding it down onto the covers.

Rex practically collapsed with relief onto the mattress, squeezing Emmet's hand tightly. Lucy moved forward with him, leaning down and placing small, tender kisses all over his face as she began undoing the buttons of his sleeveless shirt.

Rex made a quiet, involuntary noise, and Emmet twined their fingers together. The simple, affectionate gesture immediately made Rex's muscles untense, and he sighed deeply. He hadn't realized how much stress he had been under until it had evaporated.

Lucy began slowly pulling Rex's collared shirt off of him. He only let go of Emmet's hand for a moment to free his arm, before resuming his firm grip. He reached up with his other hand, slipping it out of his shirt as well, and let it gently rest on Lucy's back. She gave a soft, happy hum, resting her forehead against his, his shirt falling to the floor.

Rex sat there for a moment, until his chest was rising and falling evenly again under his tank top.

Finally, he let his eyes open again.

Lucy was still there, so close he could feel her breath against him. She beamed at him, her eyes telling of buried laughter.

Rex glanced to his right. 

Emmet sat there beside him, sheets tangled around himself. He was staring at the two of them with a starstruck expression, mouth slightly open. 

Rex let go of Emmet's hand and reached up, resting his fingers under his chin, and gently closed his mouth.

There was a moment where all they could hear was their own hearts pounding.

And then, all three of them were laughing.

"H-holy shhh…!" Rex trailed off, shooting Emmet an apologetic look. Fortunately, he didn't seem to have noticed. 

"_ Wo-ooo-o-oow _ . Just… WowWow." Emmet shook his head, chuckling as he rubbed his face with a hand. " _ Uuuuugh _."

"I'm sorry, I'm sorry! I might have gone a little overboard there!" Lucy's face was a shade of bright pink that rivaled her hair.

"Ya _ think _ ?" Rex grinned at her, gesturing dramatically. "I _ literally _ almost collapsed on the floor. A little warning next time??"

"We can go slower than that! I just… g-got carried away…" She looked down at her feet, biting her lip as her smile crumpled slightly. 

Rex felt his own grin fall a little. He reached out and ran his fingers through her hair gently, startling her. "Hey, hey. You're fine. Everything's okay."

She looked up and gave him a small half-smile. 

"... Everything is awes--?"

Lucy and Rex simultaneously punched Emmet's arms, causing all three of them to fall into another round of laughter. 

Emmet cowered in mock fear, lifting his arms as if to block another blow. "Ouch! Ahh, sorry!! I'll stop joking around!!"

Lucy roughly ruffled his hair, earning an overdramatic noise of distress. 

Rex settled back on his hands as his laughter subsided, looking between Emmet and Lucy with a broad smile.

And as he looked at them, his heart suddenly gave a harsh pang.

Ah crap… Why did he have to start getting emotional _ now? _

"So!" He said quickly, bringing their attention back to him. "Am I staying in my clothes here, or what?" He pulled off his tank top and balled it up, tossing it at Lucy. 

Without hesitation she caught it, twirled it between her hands, and harmlessly whipped one of his pecs with it.

He flinched, caught completely off guard. "Wh--Hey! What the-- I'm _ trying _ to be sexy here!!"

"There!" She dropped his undershirt on the floor, resting a hand on her hip. "_ Now _ we're even. ~" 

He turned to Emmet, opening his mouth to voice his indignation, just to catch the other man quickly turn in the other direction, his face red. 

Wh-?... _ Oh _ . Ohoh… Well _ that _ had been easy. 

Rex couldn't keep a smirk off of his face as he watched Emmet's blush slowly spread over his face. 

"... You do know you can touch 'em, right?" 

Emmet tensed, sputtering slightly, turning further from Rex and shrinking away. "I… have no idea what you mean…!" 

His grin widened. "Don't pretend you weren't totally checking out my abs just now."

Emmet shook his head so quickly his hair flipped back and forth, confirming Rex's suspicions.

Rex took Emmet’s hand by the wrist. Emmet tried to tug away from him, but Rex tightened his grip slightly, and he immediately stopped resisting. 

Rex pulled his hand towards him, gently resting it on the toned muscles of his stomach before letting go. 

Emmet inhaled sharply, lifting his hand away, just his fingertips brushing against him. After a moment's hesitation, he let his palm lower again, one finger gently tracing the outline of the defined muscles.

Rex felt his cheeks darken slightly, but remained in his comfortable reclined position, acutely aware of Emmet's touch as he curiously followed the lines over his abdomen.

"Yeah, they're pretty sweet, huh?" Rex said in what he hoped was a casual tone, turning to grin at Lucy as she sat on the other side of him. She rolled her eyes, but grinned back, leaning against him slightly. 

Emmet glanced over at him, giving a small nod, his sweet, flustered smile causing Rex's heart to skip a beat or two. He huffed softly through his nose, looking down shyly. "Y… yeah…" 

… 

Rex slowly stood, pulling away from the two of them, to their surprise.

His back still partially to them, Rex began undoing his belt, trying to keep his movements and expression calm and casual. With how quickly both his mind and heart were racing, however, he wasn't too sure how well he was pulling that off. 

He caught movement out of the corner of his eye, Lucy scooching closer to Emmet on the bed. He could tell their wide eyes were trained on every movement he made.

He unthreaded his belt from the loops, coiling it up and setting it on the bedside table.

Their eyes followed his hands.

His heart jumped to his throat as he took hold of the waist of his pants, fumbling with the button. Once again he fixed his attention solely on his breathing, blocking out anything else in his concentration.

In a moment his pants were undone, in the next he was sliding them off of his legs.

Left in his plain gray boxers, he suddenly felt very exposed. He tried to look relaxed as he folded his pants over his arm, setting them down on the floor. 

He decided he could finally risk a glance back at Lucy and Emmet. 

They wore almost identical expressions of flustered excitement. Emmet was holding Lucy's arm tightly. His eyes widened slightly as he and Rex made eye contact, and he hid his face behind Lucy's shoulder. Rex snorted with laughter, raising a brow at Lucy. She met his gaze, a slow smile spreading across her face.

She crooked a finger, beckoning him over. 

Rex obediently followed this command, walking over until he was standing right in front of them. 

Lucy gently nudged Emmet with her elbow. He lifted his head, eyes opening even wider. She nodded slightly at Rex, who then realized he had no idea what to do with himself. He stood there with his arms against his sides, hands flexing subconsciously, looking between his partners with a nervous attempt at a grin.

Lucy rose and moved to stand at Rex's side, wrapping her arms around his neck, leaning against his shoulder and placing a kiss on his cheek, causing him to flush happily. She then rest her hands and cheek on his shoulder, giving a content sigh. 

Emmet was much more hesitant.

He stood slowly, unable to look at Rex's face, instead looking down at the sheets bunched in his hands. Rex didn't move, not wanting to scare him.

Geez, poor Ems… He really was even more nervous than Rex was, huh?

Emmet finally glanced up, biting his lip, eyes flicking between Lucy and Rex. Rex gave him what he hoped was an encouraging smile, and was certain Lucy did the same. 

Emmet lowered his gaze again, taking a deep, calming breath… and let go of the sheets.

In another moment his arms were around Rex's waist, and their mouths met softly.

Rex didn't hesitate this time, wrapping his arms around Emmet and holding him close.

Emmet's kiss was gentle, uncertain. His lips barely brushed over Rex's before interlocking with them, the pressure tentative. In answer, Rex buried a hand in Emmet's hair, pulling him slightly deeper into the kiss. Emmet's arms tightened around his waist as he inhaled sharply through his nose, giving a soft shiver. The slight motion caused something to stir in Rex, and he gently bit Emmet's lip, earning a quiet, irresistible moan in response.

Rex let whatever was in him take control, no longer aware of his actions, and no longer caring. He practically melted into the embrace, taking Emmet's face in his hands, bringing their mouths together again and again… each kiss as sweet and intoxicating as the last. 

Emmet couldn't suppress his soft sounds of pleasure, and after a while, he stopped trying to. Rex felt Emmet's hands moving down his back without really noticing them, barely registering him take hold of the waistband of his boxers.

He felt a hand rest atop his on Emmet's cheek, their fingers twining as Emmet bent down. He let Lucy lead him back onto the bed, leaning against her slightly as she sat behind him. Emmet followed, stepping over the discarded clothes on the floor. Lucy wrapped her arms around Rex's chest, burying her fingers in the fine hair there, kissing his neck, his shoulders, his jawline, holding him steady as Emmet knelt in front of him, leaning over with a soft sigh of longing. 

And Rex closed his eyes, letting himself be taken by this shining moment, overwhelmed and overcome with their combined passion, and with the knowledge that he adored them just as much.

And for the first time since he could remember… Rex felt truly happy... 

And truly _ loved. _

\-----

Rex opened his eyes slightly, scowling in the sunlight. How was it that the one gap in the blinds always managed to line up perfectly with his face? He was exhausted, he ached all over… He must have worked out too hard… He just wanted a few moments more sleep. He tried to lift an arm to shield his eyes, only to find it pinned to his side. 

He glanced down in surprise, momentarily disoriented as he was faced with a head of ruffled brown hair… And then the events of the night before came rushing back to him. 

Emmet had his arms wrapped around Rex in a bear hug, his cheek pressed up against his shoulder. Rex looked on his other side and found Lucy snuggled up against him, using his lifted arm as a pillow, one hand resting gently on his bare chest.

Rex felt a warm, genuine smile stretch across his face. He bent his raised arm a little and lightly pet Lucy's hair. She stirred slightly, giving a sleepy sigh, repositioning her head on his arm. He turned his head and gently rested his cheek on the top of Emmet's head, closing his eyes contentedly. 

Yeah…

Stupid clichés be damned.

Everything really was awesome.


End file.
